One person will draw a detail, then the next person adds on to it. You have to save the previous picture to add on to it though.
Ex:
Jdogg draw a line Jdogg1 draws another line Jdogg2 turns it into a square.
So don't add a ton of detail at a time. 1, 2, or 3 small things. When you add on you can make the picture bigger. For this thread I reccomend using MS Paint because you are just making small details.